[INFO] fetching crate low 0.0.0...
[INFO] checking low-0.0.0 against master#8007b506ac5da629f223b755f5a5391edd5f6d01 for pr-88041
[INFO] extracting crate low 0.0.0 into /workspace/builds/worker-21/source
[INFO] validating manifest of crates.io crate low 0.0.0 on toolchain 8007b506ac5da629f223b755f5a5391edd5f6d01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8007b506ac5da629f223b755f5a5391edd5f6d01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate low 0.0.0
[INFO] finished tweaking crates.io crate low 0.0.0
[INFO] tweaked toml for crates.io crate low 0.0.0 written to /workspace/builds/worker-21/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8007b506ac5da629f223b755f5a5391edd5f6d01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8007b506ac5da629f223b755f5a5391edd5f6d01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-21/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-21/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+8007b506ac5da629f223b755f5a5391edd5f6d01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 40b668007586fa140181678d68baaaa6d1441b61f680f640925d21fda76c3285
[INFO] running `Command { std: "docker" "start" "-a" "40b668007586fa140181678d68baaaa6d1441b61f680f640925d21fda76c3285", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "40b668007586fa140181678d68baaaa6d1441b61f680f640925d21fda76c3285", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "40b668007586fa140181678d68baaaa6d1441b61f680f640925d21fda76c3285", kill_on_drop: false }`
[INFO] [stdout] 40b668007586fa140181678d68baaaa6d1441b61f680f640925d21fda76c3285
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-21/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-21/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+8007b506ac5da629f223b755f5a5391edd5f6d01" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 943fe1ac0bedf805bc00a44ab2f399f3bc7b346a2366c5891608069f3df2552e
[INFO] running `Command { std: "docker" "start" "-a" "943fe1ac0bedf805bc00a44ab2f399f3bc7b346a2366c5891608069f3df2552e", kill_on_drop: false }`
[INFO] [stderr]     Checking low v0.0.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.22s
[INFO] running `Command { std: "docker" "inspect" "943fe1ac0bedf805bc00a44ab2f399f3bc7b346a2366c5891608069f3df2552e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "943fe1ac0bedf805bc00a44ab2f399f3bc7b346a2366c5891608069f3df2552e", kill_on_drop: false }`
[INFO] [stdout] 943fe1ac0bedf805bc00a44ab2f399f3bc7b346a2366c5891608069f3df2552e